Blair's random numbers
Blair wrote a program that:
1) Generates 408 random integers between 7 and 109, inclusive.
2) Saves these integers to a file F.txt
Let A be the average of the integers in F.txt . What is the expected value of A ?
The answer is 58.
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1 solution
The answer is 58 .
The random number generator will generate all the integers between 7 and 109 with equal probability. The expected average is the mid-point of these numbers, which equals ( 7 + 1 0 9 ) / 2 = 5 8 .